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Designing g-C3N4-based nanostructured photocatalysts is crucial to boosting their application in advancing clean energy and sustainable environmental solutions. In this study, cyano groups and amorphous carbon self-modified P-doped g-C3N4 (PCNx) photocatalysts were designed and prepared by one-pot calcination. Melamine phosphate was employed as a multifunctional precursor to simultaneously achieve P-doping and amorphous carbon/cyano group self-modification in the g-C3N4 photocatalyst. The molar ratio of urea to melamine phosphate regulates the content of amorphous carbon and cyano groups, which further enhances the conductivity of g-C3N4. Due to the high conductivity of amorphous carbon and cyano groups, the charge transfer process was further accelerated. As a result, the optimized P-doping and amorphous carbon/cyano-group in PCN2 photocatalyst led to an excellent H2 production rate of 157.86 µmol·g−1·h−1 under visible light, which is approximately 2.4 times and 3 times higher than those of CN and PCN. The work developed an alternative strategy for the construction of highly efficient g-C3N4-based photocatalysts. [ABSTRACT FROM AUTHOR]

Dexamethasone (Dex) is a widely used glucocorticoid in medical practice, with applications ranging from allergies and inflammation to cerebral edema and shock. Despite its therapeutic benefits, Dex is classified as a prohibited substance for athletes due to its potential performance-enhancing effects. Consequently, there is a critical need for a convenient and rapid detection platform to enable prompt and accurate testing of this drug. In this study, we propose a label-free Förster Resonance Energy Transfer (FRET) aptasensor platform for Dex detection utilizing conjugated polymers (CPs), cationic conjugated polymers (CCPs), and gene finder probes (GFs). The system operates by exploiting the electrostatic interactions between positively charged CCPs and negatively charged DNA, facilitating sensitive and specific Dex detection. The label-free FRET aptasensor platform demonstrated robust performance in detecting Dex, exhibiting high selectivity and sensitivity. The system effectively distinguished Dex from interfering molecules and achieved stable detection across a range of concentrations in a commonly used sports drink matrix. Overall, the label-free FRET Dex detection system offers a simple, cost-effective, and highly sensitive approach for detecting Dex in diverse sample matrices. Its simplicity and effectiveness make it a promising tool for anti-doping efforts and other applications requiring rapid and accurate Dex detection. [ABSTRACT FROM AUTHOR]

Biofertilizers with phosphate-solubilizing microorganism (PSM) inoculations have been suggested to diminish the limitation of phosphorus (P) deficiency in plants. However, their applications in agriculture are restricted due to the inconstant effects of various PSMs. Proper carriers for the inoculations may overcome this shortcoming and improve PSMs' effectiveness. The objective of this study was to investigate whether straw compost, a type of organic material, can act as a carrier for improving the efficiencies of phosphate-solubilizing bacteria and fungi named Acinetobacter sp. and Aspergillus niger, respectively, in soils. We monitored the growth and cellular physiological responses of one type of model plants, named perennial ryegrass (Lolium perenne L.), under four soil treatments, including non-fertilization, PSM inoculation alone, straw compost addition alone, and the combined applications of both PSMs and straw compost. We found the combined treatments significantly improved the growth by 14.7% for shoot height and 79.7% for shoot weight, respectively, on average. P and potassium (K) uptakes of ryegrass were also increased by 102.5% and 65.3%, respectively, after the application of both PSMs and straw compost. Furthermore, physiological properties, such as photosynthetic efficiency and P-transportation capacity, of ryegrass were also significantly improved under combined treatments when compared to other treatments, regardless of the types of PSM included. The piecewise structural equation model further indicated that PSM inoculation and straw compost input are synergistically contributing to the nutrient uptake of ryegrass through many direct and indirect ways. We propose that straw compost is a good carrier material for PSMs' survival and would improve their plant growth promotion ability in soil. Our results provide valuable insights into the exploitation and utilization of P-biofertilizers in agriculture. [ABSTRACT FROM AUTHOR]

The construction of hybrid junctions remains challenging for the rational design of visible light-driven photocatalysts. Herein, In2S3/CdS/N-rGO hybrid nanosheets were successfully prepared via a one-step pyrolysis method using deep eutectic solvents as precursors. Benefiting from the surfactant-free pyrolysis method, the obtained ultrathin hybrid nanosheets assemble into stable three-dimensional self-standing superstructures. The tremella-like structure of hybrid In2S3/N-rGO exhibits excellent photocatalytic hydrogen production performance. The hydrogen evolution rate is 10.9 mmol·g−1·h−1, which is greatly superior to CdS/N-rGO (3.7 mmol·g−1·h−1) and In2S3/N-rGO (2.6 mmol·g−1·h−1). This work provides more opportunities for the rational design and fabrication of hybrid ultrathin nanosheets for broad catalytic applications in sustainable energy and the environment. [ABSTRACT FROM AUTHOR]

Nowadays, multi-access edge computing (MEC) has been widely recognized as a promising technology that can support a wide range of new applications for the Internet of Things (IoT). In dynamic MEC networks, the heterogeneous computation capacities of the edge servers and the diversified requirements of the IoT applications are both asymmetric, where and when to offload and schedule the time-dependent tasks of IoT applications remains a challenge. In this paper, we propose a flexible offloading and task scheduling scheme (FLOATS) to adaptively optimize the computation of offloading decisions and scheduling priority sequences for time-dependent tasks in dynamic networks. We model the dynamic optimization problem as a multi-objective combinatorial optimization problem in an infinite time horizon, which is intractable to solve. To address this, a rolling-horizon-based optimization mechanism is designed to decompose the dynamic optimization problem into a series of static sub-problems. A genetic algorithm (GA)-based computation offloading and task scheduling algorithm is proposed for each static sub-problem. This algorithm encodes feasible solutions into two-layer chromosomes, and the optimal solution can be obtained through chromosome selection, crossover and mutation operations. The simulation results demonstrate that the proposed scheme can effectively reduce network costs in comparison to other reference schemes. [ABSTRACT FROM AUTHOR]

Phospholipase C is an enzyme that catalyzes the hydrolysis of glycerophospholipids and can be classified as phosphoinositide-specific PLC (PI-PLC) and non-specific PLC (NPC), depending on its hydrolytic substrate. In maize, the function of phospholipase C has not been well characterized. In this study, the phospholipase C inhibitor neomycin sulfate (NS, 100 mM) was applied to maize seedlings to investigate the function of maize PLC. Under the treatment of neomycin sulfate, the growth and development of maize seedlings were impaired, and the leaves were gradually etiolated and wilted. The analysis of physiological and biochemical parameters revealed that inhibition of phospholipase C affected photosynthesis, photosynthetic pigment accumulation, carbon metabolism and the stability of the cell membrane. High-throughput RNA-seq was conducted, and differentially expressed genes (DEGS) were found significantly enriched in photosynthesis and carbon metabolism pathways. When phospholipase C activity was inhibited, the expression of genes related to photosynthetic pigment accumulation was decreased, which led to lowered chlorophyll. Most of the genes related to PSI, PSII and TCA cycles were down-regulated and the net photosynthesis was decreased. Meanwhile, genes related to starch and sucrose metabolism, the pentose phosphate pathway and the glycolysis/gluconeogenesis pathway were up-regulated, which explained the reduction of starch and total soluble sugar content in the leaves of maize seedlings. These findings suggest that phospholipase C plays a key role in photosynthesis and the growth and development of maize seedlings. [ABSTRACT FROM AUTHOR]

The nonlinear flow law and soil boundaries greatly affect the dissipation process of soil consolidation. Thus, to study the impact of nonlinear flow under impeded drainage boundaries, the classical non-Darcian flow model described by non-Newtonian index was introduced. The numerical solutions are derived in detail by the finite difference method (FDM) for one-dimensional (1-D) consolidation incorporating the impeded boundaries, and the computer program is compiled. Then, comparing two analytical solutions based on Darcy's law and a numerical case of Forchheimeer's flow, the validity of the present method was verified. The numerical results indicate that there is a critical depth phenomenon for the non-Darcian flow incorporating impeded drainage boundaries. The excess pore water pressure of the soil below the critical depth dissipates more slowly than that of Darcy's law, whereas the pore pressure of the soil above the critical depth dissipates more quickly than that of Darcy's law. Moreover, considering that the non-Darcian flow with the non-Newtonian index will still delay the overall consolidation rate of the soft ground, the greater the nondimensional parameter I0 is, the more obvious the lagging phenomenon of the overall dissipation of pore pressure is. [ABSTRACT FROM AUTHOR]

Plasmids are mostly found in bacteria as extrachromosomal genetic elements and are widely used in genetic engineering. Exploring the mechanisms of plasmid–host interaction can provide crucial information for the application of plasmids in genetic engineering. However, many studies have generally focused on the influence of plasmids on their bacterial hosts, and the effects of plasmids on bacteria-feeding animals have not been explored in detail. Here, we use a "plasmid–bacteria–Caenorhabditis elegans" model to explore the impact of plasmids on their host bacteria and bacterivorous nematodes. First, the phenotypic responses of C. elegans were observed by feeding Escherichia coli OP50 harboring different types of plasmids. We found that E. coli OP50 harboring plasmid pEX18Gm unexpectedly increases the fecundity of C. elegans. Subsequently, we found that the plasmid pEX18Gm indirectly affects C. elegans fecundity via bacterial metabolism. To explore the underlying regulatory mechanism, we performed bacterial RNA sequencing and performed in-depth analysis. We demonstrated that the plasmid pEX18Gm upregulates the transcription of methionine synthase gene metH in the bacteria, which results in an increase in methionine that supports C. elegans fecundity. Additionally, we found that a pEX18Gm-induced increase in C. elegans can occur in different bacterial species. Our findings highlight the plasmid–bacteria–C. elegans model to reveal the mechanism of plasmids' effects on their host and provide a new pattern for systematically studying the interaction between plasmids and multi-species. [ABSTRACT FROM AUTHOR]

Inoculum size contributes to the invasion potential of pathogens in the soil. However, the role of inoculum size in determining the fate of pathogens in disturbed soils remains unclear. Herein, we investigated the survival rates of a bacterial pathogen, Ralstonia solanacearum, in soils subjected to heat as a simulated disturbance. Our results revealed that heating increased soil resource availability but reduced resource differentiation between R. solanacearum and indigenous bacterial communities. In both non-heated and heated soils, invader abundances increased with inoculum size, with a greater magnitude in heated soils. Inoculum size and heat-induced increases in soil-available carbon and nitrogen best predicted invasion success. Altogether, our findings suggested that the invasion by soil pathogens could be predicted by synergies between heat perturbation and inoculum size. [ABSTRACT FROM AUTHOR]

Arthrobacter pascens ZZ21 is a plant-beneficial, fluoranthene-degrading bacterial strain found in the rhizosphere. The production of the phytohormone indole-3-aectic acid (IAA) by ZZ21 is thought to contribute to its ability to promote plant growth and remediate fluoranthene-contaminated soil. Using genome-wide analysis combined with metabolomic and high-performance liquid chromatography-mass spectrometry (HPLC-MS) analyses, we characterized the potential IAA biosynthesis pathways in A. pascens ZZ21. IAA production increased 4.5-fold in the presence of 200 mgL-1 tryptophan in the culture medium. The transcript levels of prr and aldH, genes which were predicted to encode aldehyde dehydrogenases, were significantly upregulated in response to exogenous tryptophan. Additionally, metabolomic analysis identified the intermediates indole-3-acetamide (IAM), indole-3-pyruvic acid (IPyA), and the enzymatic reduction product of the latter, indole-3-lactic acid (ILA), among the metabolites of ZZ21, and subsequently also IAM, ILA, and indole-3-ethanol (TOL), which is the enzymatic reduction product of indole-3-acetaldehyde, by HPLC-MS. These results suggest that the tryptophan-dependent IAM and IPyA pathways function in ZZ21. [ABSTRACT FROM AUTHOR]

Inter-organismal metabolites play important roles in regulating organism behavior and the communication between organisms. Nematodes, the most abundant animals on earth, are crucial participants in soil ecosystems through their interactions with microbes. For example, bacterial-feeding nematodes increase the activity of indole-3-acetic acid (IAA)-producing bacteria and the IAA content in soil. However, the way in which these nematodes interact with bacteria and affect IAA biosynthesis is not well understood. Here, using the model nematode Caenorhabditis elegans and the plant-beneficial bacterium Arthrobacter pascens ZZ21, we examined the effects of nematode excretions or extracts on bacterial IAA biosynthesis. To explore the underlying regulatory mechanism in more detail, we performed transcriptome sequencing and metabolomic analysis. Our findings suggest that C. elegans extracts promote IAA biosynthesis in A. pascens ZZ21 by increasing the expression of genes and the abundance of intermediates involved in the indole-3-pyruvic acid (IPyA) pathway. C. elegans extracts also significantly influenced biosynthetic and metabolic activity in A. pascens ZZ21. Treatment with C. elegans extracts promoted pyruvate metabolism, the citrate cycle (TCA) cycle and the production of some TCA-cycle-related amino acids and inhibited oxidative phosphorylation, which induced the accumulation of reduced nicotinamide adenine dinucleotide (NADH). We propose that the extracts altered the metabolism of A. pascens ZZ21 to help the bacteria resist stress caused by their predator. Our findings indicate that bacterial-feeding nematodes mediate the interaction between nematodes and bacteria via their extracts, providing insights into the ecological function of C. elegans in soil. [ABSTRACT FROM AUTHOR]